Semiconductor substrate with interconnections and embedded circuit elements

ABSTRACT

A semiconductor substrate integrated with interconnections and circuit components. A silicon backplane is processed with silicon processing to provide electrical connectivity for circuit elements. In one embodiment functional circuit elements, e.g., MEMS, switches, filters, are integrated on the silicon backplane. In one embodiment the function circuit elements are monolithically processed into the silicon backplane. In one embodiment the silicon backplane includes interconnections for integrated circuits on different substrates to be bonded to the silicon backplane.

FIELD

Embodiments of the invention relate to silicon integrated circuits, andparticularly to interconnecting integrated circuits with other circuitelements.

BACKGROUND

Many circuits currently use discrete components and/or integratedcircuits (ICs) that may be produced with different types of processingand materials. Some of the different types of processing and materialsmay include complimentary-metal-oxide-semiconductor (CMOS),gallium-arsenide (GaAs), lithium tantalate (LiTaO₃), andsilicon-germanium (SiGe). Traditionally many of these devices have beenassembled and interconnected on ceramic or organic interconnect devicesthat have traces to interconnect the various ICs and/or passives. Theresulting interconnected circuit is then packaged as a single component.

FIG. 1 is a known example of interconnecting various ICs with aninterconnect device. Passive substrate 110 represents traditionalinterconnect devices, typically organic material (e.g., FR4) orceramics. Passive substrate 110 is passive because it has no circuitfunctionality except to assemble and interconnect the various circuitcomponents. All circuit functionality, such as processing, manipulating,affecting, etc., signals in the circuit is performed in the variouscircuit elements assembled on top of passive substrate 110. Thus, theICs, switches, and passives shown in FIG. 1 are the functional circuitelements. The main advantage to using passive substrate 110 is that itis relatively inexpensive, generally only requiring that contact padsand interconnect traces be manufactured onto passive substrate 110. Thecircuit components are then bonded or soldered to passive substrate 110.Thus, various ICs of potentially many disparate processing technologiesand/or procedures can all be packaged as a single component.

Examples of various circuit elements include RLC 120, which representsdiscrete passive components such as resistors, inductors, andcapacitors, and filters created with such passive components. Thesecomponents are used to passively process signals occurring in system100. ICs of differing processing technologies and materials are alsoshown as CMOS 130, SiGe 140, LiTaO₃ 150, and switch 160.

CMOS 130 represents ICs that are made with complimentary metal (or otherconductor) oxide semiconductor (e.g., silicon) processing. SiGe 140represents ICs that are manufactured with silicon germanium processing.Because of the differences in processing of these two technologies,processing of circuits using these different technologies occurs ondifferent substrates and interconnecting occurs on an interconnectdevice such as passive substrate 110. The use of different types ofcircuits made with the different technologies is assumed to be wellunderstood in the art, and consequently will not be discussed herein.Note that the interconnecting of ICs 130, 140, 150, and 160 may beperformed by flip-chipping the IC and bonding to bumps, or by the use ofwire bonds, as shown with SiGe 140. Additionally, the various ICs showncould be bare die rather than packaged.

LiTaO₃ 150 represents devices processed on a lithium tantalitesubstrate, which is a boutique processing technology that istraditionally used with surface acoustic wave (SAW) filters. Switch 160is shown as one traditional element that is processed using GaAs toprovide fast switching, for example, switches in radio frequency (RF)devices.

Input/Outputs 170 are used in packaging system 100. Input/Outputs 170pads or bumps use vias through passive substrate 110 to provideinterconnection to the circuitry of system 100 to the packaging ofsystem 100. The interconnection to the packaging may be through wirebonding or metal traces connecting to the packaging pins.

Despite the inexpensive interconnect provided by passive substrate 110,there may be undesired expenses in the processing of the various ICsshown in FIG. 1. For example, many ICs use boutique processingtechnologies such at LiTaO₃ or GaAs that can be significantly morecostly than silicon-based processing. However, use of these processeshas been necessary to achieve the desired performance. Integrating thesecomponents made with boutique processes with strictly silicon-basedcomponents has proven costly.

Another example of the expense in traditional practice is that manycircuits require the use of resistors, capacitors, inductors, andpassive filters. These components may be integrated directly on the IC,or they may be discrete components, such as LTCC (low temperatureco-fired ceramic) devices, that require bonding to passive substrate110. However, there are costs associated with using discrete passivecomponents, as well as directly integrating passives on modern ICsmanufactured with high precision (e.g., 90 nm) processing. The higherprecision processing is used to scale ICs with active devices such astransistors, which are typically scaleable. The increased cost ofmanufacturing may be justified by the increases in performance of theresulting devices. However, higher precision processing does little ornothing to increase performance of components such as the passives thatdo not scale. Also, for devices such as voltage regulation circuits andcertain sensors, non-high-end processing is also perfectly viable forproducing circuit elements of acceptable performance, making the use ofhigh-end processing for such devices wasteful. Thus, integrating thesedevices on ICs consisting of scaleable active device with modernprocessing techniques is wasteful of processing costs as well asvaluable die real estate.

BRIEF DESCRIPTION OF THE DRAWINGS

The description of embodiments of the invention includes variousillustrations by way of example, and not by way of limitation in thefigures and accompanying drawings, in which like reference numeralsrefer to similar elements.

FIG. 1 is a known example of interconnecting various ICs with aninterconnect device.

FIG. 2 is a block diagram of a silicon substrate interconnectingintegrated electrical circuit components and interconnections inaccordance with one embodiment of the invention.

FIG. 3 is a block diagram of interconnecting ICs with a siliconbackplane having components processed on the silicon backplane inaccordance with one embodiment of the invention.

FIG. 4 is a block diagram of externally interconnecting a cappedintegrated circuit in accordance with one embodiment of the invention.

FIG. 5 is a block diagram of circuit elements on a silicon interconnectbackplane in accordance with one embodiment of the invention.

DETAILED DESCRIPTION

Methods and apparatuses are described for using a silicon backplane tointegrate and interconnect electronic components (e.g., passive, switch,filter, analog transistor, power transistor, etc.) that cannot be builton highly scalable very large scale integration (VLSI) processes in acost effective manner. With a silicon backplane device, functionalcircuit elements may be monolithically integrated on the interconnectdevice with the interconnections. In one embodiment a silicon backplanehas components and interconnects embedded in the substrate with contactsto interconnect to other ICs.

In one embodiment all components integrated directly into the silicon ofa silicon backplane are manufactured with monolithic processing.Monolithic is to be understood as being part of, or consistent with, thesingle crystalline structure of the silicon backplane. Monolithic may beunderstood as processing where the resulting integratedcomponents/interconnects are part of the silicon wafer. Another way tounderstand monolithic is that the devices integrated with monolithicprocessing are embedded in the silicon substrate (in the wafer). Thismay be, for example, in contrast to modern VLSI CMOS processes that havemany layers, such as interconnect layers on top of integrated devices.Thus, monolithic may or may not be understood as including polysilicongrown off the silicon crystal of the silicon substrate. This wouldgenerally not include devices in a silicon substrate whose processingresults in a device with layers (e.g., CMOS). Monolithic is meant toinclude the use of conductors, such as traces and contact pads. It mayalso include some active devices, for example, transistors, as discussedbelow.

FIG. 2 is a block diagram of a silicon substrate interconnectingintegrated electrical circuit components and interconnections inaccordance with one embodiment of the invention. Semiconductor substrate210 includes a semiconductor substrate in which circuit components maybe integrated or embedded, with semiconductor processing. The use ofsilicon as a semiconductor substrate is common. Semiconductor substrate210 includes external interconnection 220, internal interconnection 230,passive 240, and contacts 250.

External interconnection 220 includes traces, wells, etc., used bysystem 200 to interconnect to packaging (e.g., pins, leads), othersubstrates, etc. For example, system 200 may be interconnected withpower supply 270 to provide power to the circuits. Power supply 270 maybe from a regulated voltage source, battery (a power storage cell), etc.Power supply 270 is typically a direct current (DC) power source.Internal interconnections 230 selectively interconnect the componentsembedded in semiconductor substrate 210 with each other and/or with ICs260, which represents one or more integrated circuits that may beconnected (e.g., wire bonded, flip-chip bonded) to semiconductorsubstrate 210.

In one embodiment passive 240 represents passive component(s)monolithically embedded in semiconductor substrate 210 with the sameprocessing used to produce interconnections 220 and/or 230. Passive 240provides electrical functionality in the circuit of system 200. Thus,passive 240 may modify, filter, or otherwise process signals of system200.

Contacts 250 represents contact (bonding) pads used to interconnect ICs260 to internal interconnections 230, which in turn interconnects ICs260 to other elements of system 200. Contacts 250 may be areas of metaland/or high conductive material used to provide an area of relativelylarger size to connect, e.g., wire bonds, bumps, to the interconnectionlines/traces of internal interconnections 230. In one embodiment system200 is enclosed with an enclosing device 280. The enclosing device willbe discussed in more detail below.

FIG. 3 is a block diagram of interconnecting ICs with a siliconbackplane having components processed on the silicon backplane inaccordance with one embodiment of the invention. Silicon backplane 310is a piece of silicon that may be processed according to siliconprocessing techniques. Silicon backplane 310 is processed tointerconnect various circuit elements in a single system on an IC.System 300 may include various ICs, including CMOS 350, SiGe 360, andCMOS 370. These devices represent any type of IC that may be integratedinto system 300 with other ICs in the same packaging. In one embodimentthe components of system 300 include silicon-based devices, thusavoiding the expense of boutique processing technologies such as LiTaO₃and GaAs. However, non silicon-based IC devices may also be included insystem 300 through integration onto silicon backplane 310. These devicesmay be electrically attached to contact pads on silicon backplane 310 bybumps or wire bonding. These devices will be selectively interconnectedto each other, and to external contact pads according to the design ofthe system of which they are a part.

The footprint of interconnect lines or traces and contact (bonding)pads, bumps, etc. do not require high precision lithographic processingtechnology because they generally derive no benefit from scaling.Additionally, note that certain common circuit elements, such as passivecomponents (e.g., resistors, capacitors) do not scale, and may notrequire a high precision lithographic processing technology to beproduced. Thus, all such aspects of a silicon interconnect device may beintegrated into the silicon interconnect with the use of non high-end(e.g., 1 μm, 0.5 μm minimum feature size) processing techniques. Notethat for certain signaling requirements, traces of a larger size may infact be desirable for an interconnect device. On such devices, theprecision level of high end, state-of-the-art lithography (e.g., featuresize of 90 nm, 65 nm) is not needed; a lower precision processingtechnology may be sufficient. Additionally, the interconnects andpassives can be embedded together in a silicon substrate with many fewerprocessing steps that the numerous steps generally used in high endprocessing to produce multiple layers of circuit material (e.g.,interconnects) on top of the structures actually embedded in theoriginal substrate.

Because silicon backplane 310 includes a semiconductor substrate, in oneembodiment it can be processed to have integrated devices, makingsilicon backplane 310 more than simply a passive interconnect device.Although it provides interconnection for system 300, silicon backplane310 is also processed with components that provide electrical circuitfunctionality to system 300. For example, silicon backplane 310 mayinclude switch 320, RLC passives 330, and bulk acoustic wave (BAW)filter 340. More or fewer components may be included in siliconbackplane 310.

Note that as the interconnection aspects of silicon backplane 310 may beprocessed on silicon backplane 310 using non state-of-the-artlithographic processing, the functional elements processed on siliconbackplane 310 may also be processed with such lesser-precisionlithographic processing technologies. One advantage gained by using thesame processing steps is the reduced cost in integrating the functionalelements and interconnections with the same processing steps. Althoughthe lithographic (x-y dimensions) technologies involved may be of lesserthan state-of-the-art, processing in the vertical direction (zdimension; e.g., thin film deposition, film thickness control) may bestate-of-the-art. In one embodiment higher precision processing may beperformed on part or all of the material of silicon backplane 310 tomanufacture the integrated circuit elements.

Note that the cost of a silicon substrate used as an interconnect deviceis initially of higher cost than a corresponding organic or ceramicinterconnect substrate. The materials of traditional interconnectsubstrates are cheaper than silicon, and the processing to produce theinterconnection is more expensive in silicon, even when using lower-endlithographic precision processing techniques. However, the cost of asilicon substrate interconnect becomes justifiable when functionalcircuit elements may be manufactured in the silicon backplane, removingsome or all of the need for discrete passive components. Cost reductionmay also be achieved by having a substrate in which to processsilicon-based components as replacements for some ICs produced withboutique processing. By eliminating the need to place some or all highreal-estate passives on ICs manufactured with high-end processingtechnologies, or use discrete passive components that must be integratedonto a system, along with replacing ICs produced with expensive boutiquetechnologies, the overall system costs may actually be lower. With theseother costs reduced, the additional cost of the silicon backplane overthe passive substrates is more than offset by the savings.

For example, one of the savings potentially achieved by the use ofsilicon backplane includes the fact that the level of lithographicprecision for the embedded devices may be accomplished on equipment thatmay not be state-of-the-art. Thus, previous generation equipment couldbe used to produce circuit elements that may otherwise be lessefficiently produced on high-end equipment that may be better used toproduce highly scalable circuit elements. The production of a system ona single chip may be effectively accomplished by using nonstate-of-the-art lithographic equipment to produce silicon backplane 310with its embedded circuit elements and interconnections, andinterconnect scalable ICs produced with state-of-the-art equipment.

In one embodiment switch 320 includes a micro electromechanical (MEMS)switch processed on silicon backplane 310 using non high-endlithographic processing. Low insertion loss MEMS switching is known forswitching, e.g., between channels of an RF module. RLC passives 330include discrete elements as well as RLC passive filters for processinginput signals. BAW 340 is a film bulk acoustic resonator, which is asilicon-based equivalent of a SAW filter used as an alternative toLiTaO₃ SAW filters. SAW filters cannot be monolithically integrated intosilicon because they are made with LiTaO₃; therefore, these and othercomponents built with boutique processing technologies will remaindiscrete components, instead of being able to be integrated on siliconbackplane 310.

The use of silicon backplane 310 allows for the design of system 300with state-of-the-art processing technologies to produce ICs that havescaleable circuit components, while allowing offloading of some circuitfunctions to functional circuit components integrated into siliconbackplane 310 that may not have such exacting requirements formanufacturing.

Because MEMS devices are generally hermetically sealed, in an embodimentwhere MEMS device(s) are used, system 300 is capped with lid 380. Lid380 may be, for example, a silicon, or silicon-based structure that canbe affixed to the material of silicon backplane 310.

FIG. 4 is a block diagram of externally interconnecting a cappedintegrated circuit in accordance with one embodiment of the invention.System 400 is similar to that discussed above in FIG. 3. In oneembodiment silicon substrate 410 includes MEMS 430 and passive 440integrated directly on silicon substrate 410. MEMS 430 and passive 440are merely examples of functional circuit elements that may be embeddedon silicon substrate 410, and are not meant to be restrictive orexclusive of circuit elements that may be embedded in silicon substrate410.

System 400 also includes exemplary ICs 460 and 470. IC 460 is shownbonded with bumps, and IC 470 is shown bonded with wire bonds. It is tobe understood that more or fewer ICs may be included in system 400, andthe various ICs may be bonded with bumps, wire bond, or other methods.Interconnections 450 represent the selective internal connections amongthe devices of system 400. For example, IC 460 may be interconnected toMEMS 430, while IC 470 may not be, etc. Interconnections 450 may alsoinclude traces/lines to interconnect IC 460 to IC 470. In one embodimentit will be advantageous for system 400 to have cap 480 over thecircuitry.

System 400, once integrated with all of its components, is packaged asan IC in accordance with embodiments of the invention. An IC willtypically have electrical connectivity points such as pins/leads oninline or quad packages, or balls on a ball-grid array (BGA) package. Toconnect system 400 to its packaging, system 400 is provided withexternal interconnection mechanism(s). Through these interconnectionssystem 400 is able to interface with other ICs, other circuitry, powersupplies, etc. In one embodiment silicon substrate 410 is processed withexternal interconnection 420. If system 400 includes cap 480, externalinterconnection 420 may extend from the internal region of system 400that is capped to outside the cap. External interconnection 420 is thenbonded to the intended packaging of system 400 via, e.g., wire bonds421. The use of wire bonds to connect an integrated circuit to itspackaging is known.

In one embodiment system 400 includes cap 480, and vias 422 drilled oretched through cap 480 to external interconnection 420. Externalinterconnection 420 is manufactured directly on silicon substrate 410 toprovide external connectivity, as with the other interconnectiontechniques described above. Vias 422 may be, e.g., insulated and thenfilled or coated with metal and/or have a wire bond used to connect tointerconnection 450. It is again to be understood that theinterconnections described here may be used alone or in combination, andthe description herein is not intended to be limiting regarding a mannerto interconnect system 400 to an external connection point.

In one embodiment system 400 is manufactured with silicon vias 490through silicon substrate 410 to contact pads for the externalinterconnections. Vias 490 are typically drilled or etched throughsubstrate 410, insulated, and filled or coated with metal to provideelectrical connectivity between the contact pads and, for example,conductive traces to the pins, pads, or balls of the packaging.

FIG. 5 is a block diagram of circuit elements on a silicon interconnectbackplane in accordance with one embodiment of the invention. Theelements of FIG. 5 are not intended to be shown to scale. In oneembodiment the elements on silicon backplane 510 are part of a highlyintegrated radio module. Silicon backplane 510 includes high voltagechip (HVC) 520 and radio frequency IC (RFIC) 530. HVC 520 represents anintegrated circuit (whether separate IC(s) or embedded in siliconbackplane 510) that provides the high voltage necessary to actuate someMEMS devices. In a radio module, RFIC 530 may refer to multiple separatecomponents of the radio module, as with a multimode radio module.

Power amplifier (PA) 590 represents a final stage of an RF transmitterthat drives an antenna attached to the circuit on silicon backplane 510,in the embodiment where silicon backplane 510 includes an RF module. PA590 may be an IC bonded to silicon backplane 510. PAs are generally GaAsor SiGe devices and typically require passive matching and tuningnetworks for maximum efficiency and radiation by the antenna. Thesematching networks can be processed in silicon backplane 510 while one ormore die encompassing PA 590 are connected to silicon backplane 510 withflip chip or wire bonding. HVC 520, RFIC 530, and PA 590 are typicallyintegrated circuits that will be integrated together in a radio moduleon an interconnect device. These ICs may be integrated on siliconbackplane 510 with either wire bond or flip chip bonding. These elementsare meant only for purposes of illustration, and other ICs, includingICs unrelated to a radio module, may be included. In one embodimentthese ICs represent any kind of IC desirable for a system on a chipdesign.

In one embodiment silicon backplane 510 includes several componentsintegrated directly on silicon backplane 510 through silicon processing.For purposes of illustration, and not by way of limitation, siliconbackplane 510 may include balun 540, BAW 550, passives 560, and MEMSswitch 570. Balun 540 represents the many components that make up thecircuitry to transform an incoming single-ended radio signal to adifferential signal. Because the separate elements of balun 540 aretypically components that do not scale, they can be manufactured withthe lower-end processing with which silicon backplane 510 ismanufactured. This provides good reason to integrate them directly ontosilicon backplane 510 rather than as discrete components, or integratedon other ICs.

BAW 550 represents multiple SAW filters made of MEMS in the silicon ofsilicon backplane 510. In one embodiment BAW 550 is a film bulk acousticresonator (FBAR) filter. BAW 550 represents what may be multiplediscrete BAWs in the system. As with the BAW components, anothercomponent that can be processed directly into the silicon of siliconbackplane 510 is passives 560. Passives 560 represents discreteresistors, capacitors, and inductors that may be present in anintegrated circuit system, as well as LC filters that are typicallypresent in radio modules. In one embodiment the silicon of siliconbackplane 510 is high resistivity silicon. Thus, the passives may bemanufactured of low-impedance conductor on high-resistivity silicon,which provides better performance in passives 560. The propermanufacturing of the components will result in high-Q passives 560integrated directly into the silicon of silicon backplane 510.

As part of a radio module, or as part of another system integrated on asingle die, silicon backplane 510 may include other circuit components,including, but not limited to: MEMS 581, voltage regulation 582, andoptical 583. MEMS 581 is intended to represent a broad range of MEMSdevices that may be integrated on an IC. For example, MEMS 481 mayinclude: microfluidic devices with fluid channels, fluid storage(radiators), recombiners, microchannel cooler, and pumps; actuationdevices used to trigger events due to force, inclining of a device inwhich the system is found, etc.; and electrical and/or biological sensorcircuits.

Voltage regulation 582 includes regulation circuits to filter noise outof a voltage supply, or convert one voltage to another. Additionally,voltage regulation 582 may include circuits that regulate a non-steadyvoltage supply into a regulated voltage level.

In one embodiment silicon backplane 510 also includes optical devices583. This includes, but is not limited to, fiber alignment channels,laser components, etc. In one embodiment silicon backplane is made ofhigh-resistivity silicon, which looks like glass to infrared opticalsignals. Thus, the use of high-resistivity silicon may be advantageouswhen optical devices 583 are included in silicon backplane 510. In eachof optical 583 and voltage regulation 482, note that these circuits maylend themselves to have active devices, such transistors, diodes, etc.

Although active devices may typically be scaleable, in various circuits,such as embodiments of the circuits mentioned here, active componentsmay be manufactured with non high-end processing technologies because ofthe nature of the components needed. For example, voltage regulationwill typically require larger transistors that can be adequatelymanufactured for the purposes they serve in their respective circuitswith less precise lithography. Thus, even with what may be considered tobe scaleable components may be integrated on silicon backplane 510. Inone embodiment such active components may be monolithically processedwith the interconnections and other circuit elements integrated onsilicon backplane 510.

Reference herein to “one embodiment” or “an embodiment” means that aparticular feature, structure or characteristic described in connectionwith the embodiment is included in at least one embodiment of thepresent invention. Thus, the appearance of phrases such as “in oneembodiment,” or “in another embodiment” describe various embodiments ofthe invention, and are not necessarily all referring to the sameembodiment. Besides the embodiments described herein, it will beappreciated that various modifications may be made to embodiments of theinvention without departing from their scope. Therefore, theillustrations and examples herein should be construed in anillustrative, and not a restrictive sense. The scope of the inventionshould be measured solely by reference to the claims that follow.

1. An interconnect apparatus comprising: a silicon substrate; contactpads processed on the silicon substrate to connect to an integratedcircuit (IC) die; interconnections selectively interconnecting thecontact pads, the interconnections monolithically processed on thesilicon substrate; and circuit elements monolithically processed on thesilicon substrate in the same plane as the interconnections with thesame processing as the contact pads and the interconnections, thecircuit elements to interoperate with the IC die, wherein the circuitelements include a micro electro-mechanical system (MEMS) device.
 2. Aninterconnect apparatus according to claim 1, wherein the MEMS devicefurther includes a microfluidic system.
 3. An interconnect apparatusaccording to claim 1, wherein the MEMS device further includes anactuation circuit device.
 4. An interconnect apparatus according toclaim 1, wherein the circuit elements comprise a sensor circuit.
 5. Aninterconnect apparatus according to claim 1, wherein the siliconsubstrate comprises a high-resistivity silicon substrate.
 6. Aninterconnect apparatus according to claim 5, wherein the circuitelements comprise optical circuit components.
 7. An interconnectapparatus according to claim 1, wherein the circuit elements comprise anactive circuit element.
 8. An interconnect apparatus according to claim1, further comprising a cap processed onto the silicon substrate tohermetically isolate circuit elements on the silicon substrate.
 9. Aninterconnect apparatus according to claim 8, wherein the cap comprises acap of silicon-based material.
 10. An interconnect apparatus accordingto claim 8, further comprising interconnect vias manufactured in the capto provide electrical connectivity to contact pads on the siliconsubstrate.
 11. An integrated circuit chip having a circuit element on asubstrate created with a first lithographic processing interconnected ona silicon interconnect substrate having functional circuit elementsmonolithically embedded in the interconnect substrate in the same planeas interconnecting elements, created by the process of: processingcontact pads and electrical traces monolithically on the siliconsubstrate with a second lithographic processing to interconnect thecircuit elements; processing the functional circuit elementsmonolithically on the interconnection substrate with the secondlithographic processing, to create the circuit elements in the sameplane as the contact pads and electrical traces; processing a microelectro-mechanical system (MEMS) device monolithically on theinterconnection substrate with the second lithographic processing; andinterconnecting the circuit element of the first lithographic processingon the separate substrate to contact pads on the interconnectionsubstrate to interconnect the circuit element of the first lithographicprocessing with the functional circuit elements of the secondlithographic processing.
 12. An integrated circuit chip according toclaim 11, wherein the circuit elements comprise an active circuitelement.
 13. An integrated circuit chip according to claim 11, whereinthe circuit elements on separate substrates comprise circuit elementsall on silicon substrates.
 14. An integrated circuit chip according toclaim 11, wherein the silicon interconnect substrate further comprises asilicon lid to hermetically seal functional circuit elements.
 15. Anintegrated circuit chip according to claim 14, wherein the lid furthercomprises interconnections through the lid to interconnection contactpads on the silicon interconnect substrate.
 16. An electronic systemcomprising: a chip with an integrated circuit (IC) bonded to contactpads on a silicon interconnect backplane, the silicon backplane havingintegrated circuits including a micro electro-mechanical system (MEMS)device processed into the silicon backplane with the same processingused to create the contact pads, the processing different from aprocessing used to create the IC; and a direct current power storagecell coupled with the chip to supply power to the chip.
 17. A systemaccording to claim 16, wherein the MEMS device further includes amicrofluidic system.
 18. A system according to claim 16, wherein theMEMS device further includes an actuation circuit device.
 19. A systemaccording to claim 16, wherein the circuit elements comprise sensorcircuits.
 20. A system according to claim 16, further comprising a capprocessed onto the silicon backplane to hermetically isolate circuitelements on the silicon backplane.
 21. A system according to claim 20,wherein the cap comprises a cap of silicon-based material.
 22. A systemaccording to claim 20, further comprising interconnections manufacturedthrough the cap to provide electrical connectivity to contact pads onthe silicon backplane.